Download Science Focus 10 Chapter 11 Review KEY

TR 11-66
MHR • Unit 4 Energy Flow in Global Systems
✓ SEC T I O N 1 1.3 A SS E SS M E N T I D EA S
• The Check Your Understanding questions provide
one assessment option.
• Use BLM 11-10 Chapter 11 Test/Assessment to
assess students’ understanding of this chapter.
7.
Increase in
global temperature
Water absorbs solar
radiation (has lower
albedo than ice)
Melting of sea ice
CHECK YOUR UNDERSTANDING ANSWERS
Student Book Page 430
1. (a) Paleoclimatology is the study of ancient or past
climates.
(b) Paloeclimatologists conduct tree-ring analyses,
study fossils and pollen grains, analyze ice core
samples and glacier ice, and study historical documents.
2. The climate across Canada 6000 years ago was
much like the climate today in the Canadian Arctic:
The temperature was cooler and the air was drier
than it is now.
3. The theory of continental drift explains how the
landmass consisting of modern day North America
moved toward the North Pole. The movement
could have caused the tropical climate of Canada
225 million years ago to have cooled and become
drier (more temperate). Also, the movement of the
tectonic plates would have caused ocean basins to
open and close, thereby affecting the transfer of
thermal energy on Earth’s surface, and consequently wind and precipitation patterns.
4. An asteroid striking Earth’s surface could cause a
dramatic climate change by putting large amounts
of dust, ashes, and smoke particles into the atmosphere. The resulting cloud might have blocked
sunlight from reaching Earth’s surface, causing a
drop in photosynthesis and temperatures. The build
up of carbon dioxide in the atmosphere might then
have caused temperatures to rise again.
5. Plants and animals are adapted to specific biomes. If
their environments were to change gradually, some
individuals would survive to reproduce and eventually some species would become adapted to the new
conditions. However, if climatic change were sudden, such as a sudden change in global temperatures, most plant and animal species would not have
time to become adapted to the new environmental
conditions, and would likely become extinct.
6. If Earth’s tilt decreased from 23.5º to 22.3º, then
the poles would receive less solar radiation. This
would make the climate in Alberta colder.
8. Thinking Critically Climate projections are only
as good as the models. Models based on the past do
not take into account any human factors that may
be having a major effect on our climate since they
did not really exist before the Industrial Revolution.
CHAPTER AT A GLANCE ANSWERS
Student Book Page 431
(a) A climatograph is a graph of a region’s average
monthly temperature (in ºC) and total monthly
precipitation (in mm). Months go on the x-axis,
precipitation, on the left y-axis, and temperature
on the right y-axis. The range of values used is
generally 0 to 180 mm for precipitation, and
–35ºC to 25ºC for temperature.
(b) Humidity is the amount of water vapour in the
air, and is usually reported as a percentage of the
maximum amount of water vapour that the air
can contain, given its specific temperature. The
dew point temperature is the temperature at
which the water vapour in an air mass begins to
condense.
(c) The biosphere (the region of Earth where living
things exist) includes parts of the lithosphere,
hydrosphere, and atmosphere. The biosphere is
further organized into biomes (geographic
regions with a consistent climate within their
borders that results in characteristic plant and
animal life); ecosystems (communities of living
organisms that interact with each other and with
the non-living things in the environment); and
habitats (where organisms live).
(d) The temperature drops at higher altitudes
because solar radiation warms the ground, but
not the air. Warm air masses on the ground are
forced up the mountainside. With increasing
heights the pressure drops, thus the air mass
expands. When an air mass expands and no
energy is added, the air cools.
Chapter 11 Climate and Biomes • MHR
(e) The six major biomes are:
– Tropical rain forest: consistently high temperatures and high rainfalls, much biodiversity
– Temperate deciduous forest: experiences four seasons and has the second highest rainfall
– Taiga: colder than the deciduous forest and
experiences less rainfall, less biodiversity
– Grassland: has wide shifts in temperature with
lower rainfall that cannot support large trees
– Desert: may be hot or cool, but characterized
by low rainfall; extremes of day/night temperatures
– Tundra: could be considered a very cold desert;
low rainfall and ground that remains partially
frozen year-round
(f) The examples students give will vary. In general,
a physiological adaptation is one that has
occurred within an organism and helps the
organism to survive in its environment, such as a
ground squirrel’s ability to hibernate.
A structural adaptation is a physical feature of
an organism that helps it to survive in its environment, such as the spines (modified leaves) of
a cactus, which discourage browsing animals.
A behavioural adaptation is a characteristic
behaviour of an organism that helps it to survive
in its environment, such as desert lizards seeking
shade during the heat of the day.
(g) An open system exchanges both matter and
energy with the surroundings, while a closed
system exchanges only energy. A biome is an
open rather than a closed system since matter
(air, water, soil) and energy enter and leave the
biome.
(h) Biomes of the same class are found in many different parts of the world because, although they
may exist on different continents, biomes of the
same class share the same latitudes, and therefore receive similar amounts of solar radiation
and precipitation. Because biomes of the same
class have the same type of climate, they support
similar types of vegetation, which in turn support similar types of animal life.
(i) While all species have adaptations that help
them to survive in their specific environments,
humans wear clothing (a behavioural adaptation)
and have developed complicated technologies
that allow them to build vehicles (which can be
used for moving from one biome to another)
and protective structures (buildings). Students
may also add that non-human species may not
be able to adapt quickly enough to survive in a
fast-changing environment.
(j) A paleoclimate is an ancient (or past) climate.
(k) Scientists measure past climate change in a number of ways, two of which are studying tree rings
TR 11-67
and fossils. The wider the ring in a tree cross
section, the wetter the growing season was that
year. By studying fossils, scientists can determine
what types of organisms lived in an area, and
from that, what the climate must have been like.
(l) Earth’s tilt can bring about climate change
because when Earth’s tilt is at its maximum
(24.5º), the poles receive more solar radiation.
This makes regions farther from the equator
warmer than at other times, when Earth’s tilt is
lesser.
(m) Weathering affects climate because chemical
weathering fixes atmospheric carbon dioxide
into calcium carbonate, thus removing this
greenhouse gas from the atmosphere.
(n) Cloud cover is caused by evaporating water, a
result of increasing temperatures. The increased
cloud cover blocks some of the solar radiation
reaching Earth, which then lowers temperatures
— a feedback mechanism.
(o) A catastrophic event could cause climate change
by drastically altering the amount of solar radiation reaching Earth in a very short amount of
time. Two such events would be meteor impacts
and volcanic eruptions, which cause an enormous amount of dust and other particles to be
released into the atmosphere, blocking out much
of the Sun and drastically lowering temperatures
in a short time.
(p) Mass extinction events:
– 245 million years ago: an estimated 80% of
species on Earth died
– 208 million years ago: beginning of the age of
dinosaurs
– 65 million years ago: mass extinction of the
dinosaurs
Prepare Your Own Summary
Students should use the method that best suits them in
understanding the concepts for this chapter. Whichever
methods they use, you may wish to check their
summaries for completeness and depth of
understanding. Some points students should include are
given here:
• The base of the pyramid could represent the biosphere. Below this would be biomes, then ecosystems, then habitats.
• Cells and biomes are similar in that both are open
systems: A cell is an open system because both energy (chemical and thermal) and matter (glucose, gases,
macromolecules) cross the cell’s boundary. A biome is
an open system because both energy (solar, thermal,
and chemical) and matter (some animals, water, and
air masses) can cross its boundaries. However, the
cell’s boundary, a semi-permeable membrane, is more
defined than that of a biome.
TR 11-68
MHR • Unit 4 Energy Flow in Global Systems
•
Biome
Location
Climate
Plant life
Animal life
tundra
– just below
– dry; long,
poles;
cold
circumpolar
winters and
in northern
short, cool
hemisphere
summers
– sparse;
include
grasses
and
sedges
– lemmings,
caribou,
arctic hare,
arctic fox,
wolf, black
flies,
mosquitoes
taiga
– directly
– snowy;
south of
long, cold
tundra;
winters, but
through
ground
Canada,
defrosts in
northern
summer
Europe, and
Asia
– conifers
predominate
– fur-bearing
and
hibernating
mammals;
migratory
species
– four distinct
seasons
with
temperatures below
freezing to
above
30°C;
moderate,
evenly
distributed
precipitation
throughout
year
– deciduous
trees;
understorey of
shade
tolerant
plants
– biodiversity
is relatively
large
compared
to tundra;
includes
mammals
such as
deer, foxes,
mice,
squirrels,
snakes, and
many
species of
birds and
insects
– 25–75 mm
precipitation
annually,
but has
long dry
season
– mainly
grasses
temperate – below 50°
deciduous latitude in
both
forest
hemispheres
grassland – various
latitudes:
North
American
prairies;
Asian
steppes;
African
veldts and
savannas;
South
American
pampas
desert
– between
– extremely
– none to
15° and 35°
dry, although
sparse;
in both
the
cacti,
hemispheinfrequent
succulents
res
rains tend to
be heavy;
temperature
varies
greatly
between
night and
day
tropical
rain
forests
– equatorial
– varies with
specific
region; in
Alberta
grasslands
have
burrowing
and ground
animals
such as
ground
squirrels,
pronghorn,
pheasants,
and
burrowing
owls
– relatively little
biodiversity;
type varies
with specific
region; in
North
American
desert there
are species
of lizards,
rattlesnakes,
desert
tortoise,
coyotes, and
gila monster
– hot and
– great
– is perhaps
humid, with
biodiversity;
the biome of
large
lush growth,
greatest
amounts of
especially in
biodiversity
precipitation
the canopy
year round
• Theories about why Earth’s climate changes include
the influence of Earth’s tilt, continental drift, weathering, catastrophic events, and environmental feedback.
• Scientists can use tree ring, fossil, and ice core analysis among other methods to study past climates. The
study of paleoclimates helps scientists to understand
what might have caused Earth’s climate to change in
the past, and therefore, how similar factors could
cause future climate change.
• The relationship among ecosystems, climate, and
biomes is intrinsic: Biomes are determined by their
climates; the type of biome determines what types of
vegetation will grow, and therefore what animals can
live there, in other words, the types of ecosystems
that the environment will support.
CHAPTER 11 REVIEW ANSWERS
Student Book Pages 432–433
Understanding Key Concepts
1. It begins to rain when an air mass reaches its dew
point temperature: When an air mass cools, thermal
energy is removed from both the air and the water
vapour it contains; at the dew point temperature,
the cooling water vapour condenses, forms a cloud,
and falls as precipitation.
2. The major biomes found in Canada include the
tundra, taiga, temperate deciduous forest, and the
grasslands.
3. The two most important factors in determining a
region’s climate are temperature and precipitation.
4. Data are usually averaged over a 30-year period in
order to create climatographs that describe the climate of a region.
5. The higher a region is in elevation, the cooler its
climate will be.
6. The same biome may exist in different locations,
latitudes, and altitudes because it is a combination
of temperature and precipitation that will ultimately
determine to which biome a region belongs. Biomes
are broad descriptions of the abiotic and biotic factors of an area — the specifics of the same biome in
different areas of the world will differ. (The savanna
of Africa and Alberta grasslands are both considered
grasslands.)
7. In a tropical rain forest biome, animals must adapt
to compete with a number of organisms, and be
able to survive the great number of predators in
addition to coping with the consistently warm temperatures and heavy rainfall. In the temperate
deciduous forest biome, competition is not quite as
fierce; survival in a changing climate is a more significant pressure for adaptation in this biome.
Chapter 11 Climate and Biomes • MHR
8.
9.
10.
11.
12.
13.
14.
15.
16.
Animals and plants will be well adapted to survive
in both the warm, moist summers and the cold winters by changing coat colour, hibernating, or storing
food.
The tropical rain forest and temperate deciduous
forest are quite similar, having multiple layers
where organisms happily live without venturing to
other layers of the ecosystem. The amount of light
that penetrates to the forest floor is also comparable
during the summer months, but in the temperate
deciduous forest, the canopy layer will lose its
leaves, allowing light to penetrate to the lower layers and thus supporting more photosynthesis at
these levels.
A biome is considered an open system because both
matter (animals, air, water, soil) and energy (solar
energy and heat) may both enter and leave the
biome.
Paleoclimatologists collect fossil, ice core, tree ring,
pollen grain, glacier ice, and sediment samples in
order to study past climates.
From the data that paleoclimatologists have collected, especially ice core and fossil data, they are able
to show that the climate has changed over time.
By correlating carbon dioxide levels with the climates of the past, scientists can develop models that
may be able to predict future temperatures that will
determine rainfall and climate.
Continental drift might cause climate change in the
following two ways: 1, Movement of the continents
and opening and closing of ocean basins would
affect the transfer of thermal energy on Earth’s surface, changing wind and precipitation patterns, and,
in the long run, climate; 2, Movement of a continent to a different latitude would affect the amount
of solar radiation it receives and thermal energy
transfers via wind and ocean currents, thus altering
the climate of the continent.
An example of feedback that might occur given a
drop in Earth’s average temperature would be the
resulting formation of sea ice, which, having a high
albedo, would reflect greater amounts of solar radiation into space than would water, furthering the
cooling of Earth’s atmosphere and the formation of
even more sea ice. This scenario is an example of a
positive feedback loop.
A volcano could affect the climate of a region by
putting large volumes of dust, ash, and smoke into
the atmosphere, which would reflect solar radiation.
This would not only reduce the amount of solar
radiation reaching Earth’s surface, but photosynthetic organisms (and thus their consumers) would
“starve.”
Natural climate change is called natural because it
is not caused by any human activity such as fossil
TR 11-69
fuel burning or clearcutting of forests.
17. Mass extinction means that an event occurred
which changed the conditions of a region so much
that many species could not adapt and thus died
out.
Developing Skills
18.
Climatograph, Unknown Location
25
180
160
140
120
100
80
60
40
20
0
15
5
–5
–15
–25
–35
J
F M A M J
Precipitation (mm)
J
A
S O N D
Temperature (°C)
(a) This biome is most likely from a tropical rain
forest. Over 600 mm of rain each year plus relatively mild temperatures all year are indicative of
a tropical rain forest.
(b) This city is likely located in the southern hemisphere.
(c) This location receives over 600 mm of rain each
year. High annual rainfall, combined with relatively mild average temperatures, is indicative of
a tropical rain forest. The inference that this
location is likely in southern hemisphere is
based on the cooler temperatures in May, June,
July, and August.
19. In order to survive the dry conditions of the grasslands, grasses must have deep root systems to reach
water, be able to survive periods of drought, and
resist transpiration.
20. Kangaroo rats probably forage at night to avoid the
extreme heat of the day. Their physiology would be
adapted to conserve water. Their kidneys are able to
produce extremely concentrated urine.
21. The effect of volcanic eruption on climate includes
the following events:
volcanic eruption → dust and ash in the air →
decreased solar radiation reaching Earth →
decreased temperature, decreased photosynthesis →
more carbon dioxide in the atmosphere → enhanced
greenhouse effect → increased temperature
TR 11-70
MHR • Unit 4 Energy Flow in Global Systems
Problem Solving/Applying
22. Alberta is currently experiencing an increase in forest fires, likely due to the currently drier conditions
in western Canada. Some areas of Canada are experiencing wetter conditions, which should reduce the
incidence of forest fires.
23. See Terrestrial Biomes-Background biome summaries in TR Section 11.2, for a complete discussion of biomes and adaptations.
24. If you find fossils of tropical plants in a desert, it
can be inferred that this region was once a tropical
rain forest.
25. As you climb to higher elevations, the air cools. In a
desert, this effect will be even more noticeable since
there is little moisture in the air to moderate temperature changes.
26. Since classifying a region into a biome depends primarily on temperature and precipitation data, a climatograph, which provides both of these data,
would be instrumental in determining the biome
classification.
27. (a) This climatograph is from the taiga biome.
(b) The climate could be described as having a very
cold and long winter, with average temperatures
well below 0ºC for over five months. The growing season is just over five months long. The
area’s precipitation, slightly over 600 mm annually, is mainly in the form of rain.
Critical Thinking
28. A variety of answers will be acceptable for this
question. Answers might include some of the following points:
– People adapt to living in biomes by dressing
according to the weather and building shelters
appropriate for the climate. In cold biomes, people must wear winter clothes, while in hot
biomes, they will wear loose white clothing to
stay cool. If the weather is cold, houses will have
thick walls and be well insulated. In a consistently warm climate, the houses will have a cooling
mechanism, or at least be able to take advantage
of breezes.
– They also adapt to different biomes by cultivating crops that grow in these areas and constructing their diet based on what they can grow. In
dry areas, grasslands and desert (near desert)
areas, drought-resistant crops are grown and irrigation systems are constructed. In the tropical
rain forest, inhabitants may live off the fruits of
the rain forest. Crops that require a long growing season and significant rainfall are grown in
the temperate deciduous forest biome. In the
tundra, the Inuit diet is based largely on meat
since there are few plants that could be cultivated
and there is such a short growing season.
29.
30.
31.
32.
– Humans adapt to living in particular biomes by
constructing their work and leisure time around
the climate. In climates where the midday is
extremely warm, work shuts down for a siesta
time, a time of rest to minimize exertion and
even further overheating. In the grasslands,
where many people are involved in agriculture,
farmers work from sunrise to sundown during
the growing season, taking their leisure time
during the non-growing season.
This topic may prove to be an interesting starting
point for a class discussion. Answers will vary, but
might include the following: Climate has influenced
civilization in many ways. The areas with the most
extreme climates are lightly populated, while the
inviting biomes that provide many opportunities for
agriculture are heavily populated. Diets, housing,
clothing, work, and leisure activities are all influenced by climate.
Deserts are generally found between 15º and 35º
North and South latitude due to the convection
currents in the three-cell model. The air that is
descending at these latitudes originated from the
warm moist air of the equator, which as it rose,
cooled and led to significant precipitation at the
equator. The now dry cool air warms as it descends,
increasing its dew point and providing little precipitation to these latitudes.
The taiga biome was important to the early exploration and development of Canada because it provided an economic reason for its exploration — the
fur trade.
A desert rabbit or hare would have to conserve
water, producing highly concentrated urine and
perspiring little if any. Its large ears would be
designed to dissipate heat effectively. Its fur would
likely be brown to blend in better with its surroundings. A hare in the tundra would likely be
white to blend in with its surroundings. It would
have a thick coat to maintain its body heat, and
would likely have small ears that would reduce heat
loss.
Have students answer the Focussing
questions at the beginning of the chapter without looking at their previous answers. How
much have they learned from this unit? Have students comment on what they have learned and what
they would still like to know.